twin cylinder

alright quick question, do twin cylinder motorcycles fire their pistons seperatley just like cars? The front piston fires first as the back on makes its cycle and then the back one fires as the first starts to make its. Cars do this so they don'tt have a stall moment like they would if all the pistons fired at once. The car wouldn't have power for this short moments and would stall. Is this the same for twin cylinders? Let me know... Thanks
 
That's what I thought, just like a car. Cool thanks man im working on this old twin cylinder as a side project for winter and I just wanted to make sure. How are these Kawasaki Vulcan 900s? It looks like it would be fun to ride
 
Depends on the engine design. I have a vertical twin Honda and even though it might seem counter intuitive the pistons move up and down together. Each cylinder fires in alternation, but there is only one coil so they get a spark on every revolution. V-twins need separate ignitions as the pistons are not synched. In line fours fire every half turn and the older ones only had two coils.
 
Depends on the engine design. I have a vertical twin Honda and even though it might seem counter intuitive the pistons move up and down together. Each cylinder fires in alternation, but there is only one coil so they get a spark on every revolution. V-twins need separate ignitions as the pistons are not synched. In line fours fire every half turn and the older ones only had two coils.

really? I have never seen an engine that had two pistons that rotated in the same direction at the same time. I would think it would be whacked out of balance so bad the vibrations would shake the engine into pieces. I need to check that out. What model engine or bike is that Cleonard?
 
Yea, it does seem kind of crazy. It's Honda CM400. A bit more research shows that as far as I know, all vertical twins are like this.

The engine has a big counterbalancer. Without that it would shake itself in to pieces in no time. It's actually pretty smooth considering.
 
I stand corrected, I looked up that crank for that bike... I'll be damned if both journals aren't the same stroke. I didn't see any balancers though. I am intrigued by this design. I just don't see how it works without crazy vibrations.

honda crank.JPG
 
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